How to Cite a Primary Source

Primary sources are firsthand or contemporary resources that come from firsthand observation or experience, such as diaries, letters or maps.

Citing primary sources can be more challenging than citing secondary (sources that interpret or analyze primary source material), so this article provides various techniques for doing just that in both MLA and APA styles.

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When writing about a topic, you need a variety of sources as evidence. Sources that provide firsthand knowledge are known as primary sources; secondary sources interpret and report on research conducted elsewhere. Primary sources often take the form of documents like diaries, letters or maps – accurate citation can be more challenging for these than for traditional articles and websites.

At times, primary sources may be located within modern edited collections like books or websites. When this occurs, it’s essential that you document the original source and inform your reader how you accessed it – including who wrote it and when; its type (diary passage, letter or memorandum); publication details for books or archives where you accessed it; or for modern edited collections the name and location.

Older primary sources may only provide you with an approximate date. To indicate this fact in your citations, either use square brackets or use “n.d.” followed by an approximation to show this is what was meant by “approximate date”.

Some primary sources are published in multiple languages. If this is the case for you, be sure to list both its language of origin and English version in your reference list. For instance, with Freud’s Studies on Hysteria you would include both its original work in italics and translation by J. Strachey in quotation marks in your reference list.


Primary sources provide researchers with direct access to their subject of investigation. Common primary sources include theses and dissertations, research-based journal articles (scholarly), government reports, symposium proceedings, original artwork, poems, photographs, speeches, letters memos diaries or interviews – among others.

Publish works according to your style guide’s guidelines; for historical documents that were not published (archival documents), follow your style guide’s recommendations when citing them in the text of your paper. When citing an archival document in text of paper, provide information about where you found it; this could include collection/record group names or numbers as well as box/archive numbers/titles as well as institutions owning it if found not online.

Before visiting an archive to inspect its contents, it is wise to speak with its librarian first. Depending on its nature and collection size, you may need to sign a confidentiality agreement or provide identification before being permitted access. In some instances, an appointment needs to be scheduled with a researcher in order to examine materials without damaging them in transit.

Utilizing primary sources is one of the cornerstones of conducting high-quality research projects, so its use should be executed with care so readers understand exactly what and where you’re referring to. Citing one incorrectly may result in your entire paper being rejected as well.

Secondary sources provide an interpretation or restatement of primary sources and tend to explain them further. As they may be difficult to find or outdated, it is wise to utilize them sparingly; when citing another author’s work with these secondary sources it should be identified with “qtd.” in parentheses in your paper’s text and as an endnote or footnote in its Works Cited list.


Primary sources can now be found online and must be cited differently than secondary sources, like books or newspaper articles. You must include both the author of the original document, its date of writing, type of document (diary passage, letter etc), as well as where you accessed it (webpage address etc).

Utilizing primary sources can be extremely valuable in research assignments as they allow students to relate directly with the topic at hand and gather first-hand evidence, enabling them to form their own opinions without interpretation from outside. Unfortunately, due to the nature of their content and lack of uniformity across websites they can be more difficult to cite accurately than expected.

Use examples like those shown in this video to help students better comprehend the difference between primary and secondary sources, such as those featured here. It describes these sources and demonstrates their correct citation in various formats (APA/scholarly journals etc). Furthermore, The Library of Congress offers many such primary/secondary source examples on its website such as historical newspapers/ magazines/ yearbooks along with archival documents/ collections of primary/secondary source examples.

Modern Edited Collections

Many modern collections of primary sources are published as edited books, such as letters or diaries written directly by people themselves; or collections of essays and articles related to one topic. When using such sources, please follow your chosen style guide’s guidelines for citing it – your Works Cited list might include such sources while in-text parenthetical citations may feature them depending on your discipline.

Some edited books feature more than one author. If your book contains multiple authors, cite them using this format: Last Name, First Name. Title of Book. Editor(s), Publisher, Publication Date. For three or more authors, include only their initials followed by “et al” instead of listing each name individually unless your discipline requires all authors be listed separately.

Alternatively, if the work in question is part of a multivolume series, include the number of the volume used as part of your citation. This will assist your reader if multiple editions exist of the same book, or if specific pages within that volume need to be referenced.

Primary sources can vary depending on your discipline, but generally include anything original or authentic such as laws, maps or newspaper reports. Documenting history may include oral history interviews conducted with confirmed historians or historical research conducted on written sources that has been confirmed by other researchers, photographs or videos that capture an event, or documentary films that recreate one. Data sets which describe specific subjects like census and economic statistics also fall within this realm of investigation. At times, articles published by academic institutions or media may also qualify as primary sources if they provide original research and analysis. For example, an interview conducted with someone with firsthand knowledge of an historical event would constitute primary source material; any interpretation from the journalist himself or herself would only serve as secondary evidence and therefore be less reliable than historical accounts of what happened.